Portable computing devices can include hard disk drives that may be damaged if the portable computing device is dropped. The hard disk drive may include a park state that the hard disk drive can enter to protect the drive and the data on the drive from damage if the hard drive experiences a shock. A portable computing device may include an accelerometer that can be used to cause the hard disk drive to park the disk heads in anticipation of an impact such as the portable computing device falling and impacting a surface such as a floor or table.